Machine for continuously forming tubes of asbestos cement



D. COLLIVA Oct. 10, 1961 MACHINE FOR CONTINUOUSLY FORMING TUBES OF ASBESTOS CEMENT 3 Sheets-Sheet 1 Filed Aug. 22, 1957 nt I Oct. 10, 1961 D. COLLIVA 3,003,553

MACHINE FOR commuousuz FORMING TUBES OF ASBESTOS CEMENT Filed Aug. 22, 1957 s SheetsSheet 2 llwelzrtap C0 LLL'va/ Oct'. 10, 1961 D. COLLIVA 3,003,553

MACHINE FOR CONTINUOUSLY FORMING TUBES OF ASBESTOS CEMENT Filed Aug. 22, 1957 3 Sheets-Sheet 3 -nited Sta p O 3,003,553 ,7 MACHINE FOR CONTINUOUSLY FORMING TUBES F ASBESTOS CEMENT Dante Colliva, Milan, Italy, assignor, by mesne assignments, to Johns-Manville Corporation, New York, .N.Y., a corporation of New York Filed Aug. 22, 1957, Ser. No.;67 9,5,83

Claims priority, application Italy Aug. 23, 1956 Claims. (Cl. 162-484) The present invention relates to a machine of the type including two units for the continuous manufacture'of tubes of asbestoscement without intermediate stopping and therefore without lost times. Such machine is characterized by a feeding device which allows to carry out automatically all the feeding, forming and discharging operations through the displacement of the movable forming units, so that the operator has only to control the lowering of said units for beginning the formation and their rising when the tube is formed. Moreover, the device allows to change the diameter of the tube to be formed without requiring registration or replacement of parts.

Further characteristics will appear from the following description with reference to the embodiment illustrated by way of example in the annexed drawings, in which:

FIG. 1 represents diagrammatically the machine with the feeding device,

FIG. 2 represent diagrammatically the machine completed with hydrodynamic control devices,

FIG. 3 represent a partial plan view of the device for stopping the forming cylinder below the movable unit, and

FIG. 4 represent an enlarged view of part of the ma chineillustrated in FIG. 2.

The machine is provided with two formingunits or devices A and B (such as described for instance in m'y Patent 2,760,413) arranged one after the other, whereby the single lower felt band 20 carrying thep'aste and hay ing a length equal to the felt band of conventional intermittent machine, passes on the two lower cylinders 1c and 1b driving it forward. 7 I

The tubes are formed by the units A andB which are lowered alternatively as moved by the pistons 2a and 2b, while the lower felt band bearing the paste still moves, said paste being deposited on either cylinder without any part thereof going astray.

Also the upper felt 21 is still in movement, as being driven forward by the two rolls 22 and 23. This felt band may be a' single one passing under the two units, or it may otherwise comprise two independent elements, one for each unit.

The device for automatically feeding the cylinders or mandrels is so formed that the empty cylinders or mandrels discharged in the rear part of the machine, can roll on two lateral guides so that all of them can pass under the two forming units and can be discharged, together with the tubes formed, inthe forward part of the machine.

The guides are inclined and subdivided into five parts;

The fixed rail 4 for the movement forward of the mandrels,

The fixed rail 7 intermediate between the two units,

The fixed rail 8 on which the mandrels the tubes formed thereon can roll at the outlet sideof the machine,

The two rails 5a and 5b, each with an upturned gate portion 5', vertically movable in correspondence to said units and connected thereto. 7 V V h Suitable gate members 6a and 6b connected to the forming units act as stops for the mandrels and cooperate with 5' to provide a gate by which the mandrels are controlled in their progress through the" machine.

2 An intermediate stop nose 9 is placed on the intermediate rail 7 and the figure shows as example the relative actuating piston 9a and the distributor 9b for the latter.

The locating devices 3a and 3b consist of rotating stars actuated through a suitable drive by opposite motors 1'04 and 10b with automatic stop at each rotation corresponding to the angle between two points of thestar.

FIG. 2 shows by way of example the automatic actuating devices according to the hydrodynamic solution, namely:

Ila-11b the rods connected to the units and bearing the noses for controlling the distributors, 12a-12b the distributors for the remote control of the motors driving the stars, 1 13a-13b the distributors for controlling the stop in the upper position and the upper inversion, 14a14b the distributors controlling the intermediate inversion, 15a-15b the distributors for controlling the raising the units, 16a-16b the manipulators for voluntary remote control for raising and lowering the units, 17 the pick-up cylinders or mandrels, having end journals of some diameter for any diameter of the said cylinders or mandrels, 18 automatic switch valves for the remote control oil, 19a-19b the pressing cylinders.

The above described apparatus is suitably supported in position by conventional structure 25 comprising a base 26 positioned on a foundation 27 with legs28 supporting cross arm 29. A plurality of members 30 joined bya cross T 31 support mechanisms associated with'the'form ing units; or devices A and B. A vat 32', in which the slurry of asbestos-cement is maintained, is seated on the foundation 27 and includes a pick up roll 33' in contact with the continuously moving felt band 20 to deposit thereon the layer of asbestos-cement pastefrom which the tubes of asbestos-cement are formed. The felt band 20 is guided during movement thereof by a plurality of rollers 34. A cleaning wheel 35 removes dirt or other, foreign matterfrom the felt band 20. Arms 36 support the guide rails 4. g i V The devices listed above, operating automatically, allow the cylinders or mandrels to roll and stop in the'desired position for following the cycle of continuous production, that is:

During formation through the unit 'B--' piston for Rolling of the cylinder with the tube formed from the locating stop 3 to the gate member 6b, Rolling of a cylinder from the gate member 6ato th nose9, Rolling of another cylinder from the gate member 6a t0- the locating stop 3a,

' During formationthrough the unit A-- Rolling of the cylinder with the tube formed from the" locating stop 3b to the guides, Rolling of another cylinder with the tube formedfronf the stop 6b to the guide 8,

Rolling of a cylinder from the nose 9 to'the' locating stop 3b.

15d, actuates' thelowering of the unit A the mandrel 17b contacts the felt band on the lower cylinder 1a and the pressing cylinders 19a contact the mandrel 17b.

During the lowering movement of the unit A, the gate portion 5 of the rail 5a liberates the mandrel 17a leaning on it, allowing the latter to roll only until it reaches the stop 6a, since the height of said gate portion is greater than the gap existing between the rail 5a and the stop 6a. When the tube being formed under the unit B has pickedup the paste existing on the felt band between the lower cylinder 1a and the lower cylinder 1b and has thus reached the desired thickness, the operator displaces the manipulator in the position lifts, thus rising the unit B, through remote control of the distributor 15b. During its upward stroke, the lower nose of the rod 11b, engaging the projection of the distributor 12b actuates the remote control of the rotation of the motor b and the consequent rotation of the star locating stop device Sb, allowing the mandrel 17 with the tube formed thereon to roll down along the rail 5 and then along the rail 8 as soon as the rail 5b reaches the level of the rail 8.

By its rotation, the-star locating stop device 3b brings one'of its projections'in a stop position toward the rolling down of the following cylinder which is introduced when the rail 5b reaches the level of the rail 7.

At the upper end of the stroke of the unit B, the upper nose of the rod 11b displaces the distributor 13b, thus effecting an automatic remote control for the inversion of movement of the unit B, which lowers again until the same nose engages the projection of the distributor 14b, which inverts again the direction of movement of the unit B bringing it again 'to the upper end of its stroke. This double movement is necessary for allowing (in the manner hereinunder explained) the mandrel 17d also to issue from the machine, together with the tube already formed thereon under the unit A. The distributor 14b, as it inverts the movement of the unit B, effects in addition the displacement of the distributor 9b, by lowering the nose 9 through the piston 9a, for allowing the mandrel 170 to roll down until it reaches the stop 6b.

During the second automatic lifting movement of the unit B the distributor 12b, as being actuated again by the lower nose of the rod 11b, causes the star locating stop device 3b to eifect a further rotation corresponding to one pitch, with the result of liberating the mandrel 17d with the tube formed thereon and taking a position such as to stop the forward movement of the mandrel 170 which is introduced as soon as the rail 5b reaches the level of the rail 7.

When the tube 17b being formed under the unit A reaches the desired thickness, the operator lowers again the unit B by the manipulator 16b and rises the unit A by bringing the manipulator 16a in the position lifts. Also this unit, as the unit B, effects automatically an upward stroke, a limited downward stroke and again an upward stroke for allowing the mandrel 17b with the already formed tube to move to the position 17d and at the same time the mandrel 17a to move to the position 17b, lifting the nose 9, displacing the mandrel formerly in the position 17b to the position 170, as well as introducing a new mandrel from the position 17a to the position 17b.

As already said, all the mandrels 17 have their end journals of the same diameter, whatever be their maximum diameter, so that there is the possibility of depositing the mandrels on the guides 4 without any particular. order or predisposition of the stops or of the control device.

The passage gap between the projection 5 of the rails 5a and 5b and the stops 6a and 6b respectively corresponds to the common diameter of said journals. It is thus certain that at each time the unit A or B reaches the upper limit of 'its stroke, it introduces a single mandrel from the position 17a to the position 17b and from the posi i n 17d to the p sition l7e respectively, automatically withholding all the others existing on the rail 4 or 5, even if the diameter of the journal is only slightly less than the diameter of the mandrels.

What I claim is:

1. A machine for continuously forming tubes of asbestos-cement comprising a plurality of alternately operative tube forming devices, means defining a guideway extending laterally past said tube forming devices to receive a plurality of empty mandrels at one side of the machine and to discharge the mandrels, with tubes of asbestos cement formed thereon, from the other side of the machine, said mandrels being normally urged toward said tube forming devices, each of said tube forming devices forming a tube of asbestos-cement on an empty mandrel, means adjacent said one side of the machine for retaining said plurality of mandrels in position to be selectively fed to said guideway for movement thereover, means for moving said tube forming devices into and out of tube forming position, means forming a part of one of said tube forming devices and moving therewith to feed at least one of said plurality of mandrels to the remaining portion of said guideway for movement thereover, a plurality of stop means along said remaining portion of said guideway, said stop means being operable to arrest the movement of said mandrels along the remainder of said guideway, said stop means operating in response to the movement of said tube forming devices into and out of said tube forming position so that said mandrels are positioned in proper sequence at said tube forming devices, and so that tubes of asbestos-cement may be continuously formed by said machine.

2. A machine for continuously forming tubes of asbestos-cement comprising a plurality of alternately operative tube forming devices, a guideway defined by a plurality of separate sections, at least one of said sections being movable in planes extending generally parallel to the other sections of said guideway, said guideway extending laterally past said tube forming devices to receive empty mandrels at-one side of the machine and to discharge the mandrels, with tubes of asbestos-cement formed thereon, from the other side of the machine, each of said tube forming devices forming a tube of asbestos-cement on an empty mandrel, means adjacent said one side of said machine for retaining a plurality of mandrels in position to be selectively fed to the remaining portion of said guideway for movement thereover, said mandrels being normally urged toward said tube forming devices, a first movable section of said guideway, feeding means comprising a first gate on said first movable section of said guideway and adapted to move therewith, a second gate on the first of said tube forming devices and adapted to move therewith, said first and second gates forming a gate means responsive to the movement of said first tube forming device to feed at least one of said plurality of mandrels to the remaining sections of said guideway for movement thereover, a plurality of stop means disposed along said remaining sections of said guideway, said stop means being operable to arrest the movement of said mandrels along said guideway, said stop means operating in responce to the movement of said tube forming devices into and out of tube forming position so that said mandrels are positioned in proper sequence at said tube forming devices so that tubes of asbestos-cement may be formed thereon, and so that tubes of asbestos-cement may be continuously formed by said machine.

3. A machine as defined in claim 2 wherein at least one of said stop means comprises a second movable section of said guideway, a third gate on said second movable section of said guideway and adapted to move therewith, a fourth gate on the second of said tube forming devices and adapted to move therewith, said third and 'fourth gates defining a second gate means responsive to the movement of said second tube forming device to feed at least one of said mandrels from an intermediate section 6 of said guideway to the second movable section and to a ing a pivotable nose for retaining a mandrel in an interfinal section of said guidew-ay. mediate position between said first and second movable 4. A machine as in claim 3 wherein a rotatable stop sections of said guideway. means is provided adjacent each of said tube forming devices for movement therewith, said rotatable stop 5 References it in the fil f this patent means having a plurality of radially extending projections for contacting said mandrels, and means responsive to the UNITED STATES PATENTS movement of each associated tube forming device for 2,7 ,413 o lliva Aug. 28, 1956 rotating each associated rotatable stop means through a FOREIGN PATENTS predetermined are. 10

5. A machine as defined in claim 4 and further includ- 598,619 Great Britain Feb. 23, 1948 

